Oval shouldn't be rotated, as hmm.. how those things from which brush is made off, are called? Well those things are set under a bit of an angle (at least with Swix brushes), and if you use it wrong way, you actually destroy brush faster, not to mention it doesn't "glide" that nicely as it would when used in right direction. Main thing to have brush working for long time is to move it properly, nice long moves pressing only in one direction, with no need for too much pressure. And then cleaning it. Believe it or not, easiest and best way to clean it, is just to slide it down over edge of table (some 45 deg to table, and brush it down, right way), so wax and dirt particles, sort of fly away. With normal nylon and bronze brushes you can do this once in a while, with soft brushes used for fluoro powders, it's basically after every use, as there's much more "dirt" in brush when brushing fluoro powders away.